Method and apparatus for dry cleaning



Aug" 16, 1949. M. T. HOFFMAN METHOD AND APPARATUS FOR DRY CLEANING S Sheets-Sheet 1 Filed Aug. 8, 1944 Inven tor MAM/JR ED T HoFMAN y fifimW ii'orneys 1949. M. T. HOFFMAN 2,479,358

METHOD AND APPARATUS FOR DRY CLEANING 7 Filed Aug. 8, 1944 5 Sheets Sheet 2 Inyenfor MAwRep T HO A rymW w A T101217 eys Aug. 16, 1949. M. T. HOFFMAN METHOD AND APPARATUS FOR DRY CLEANING 3 Sheets-Sheet 5 Filed Aug. 8, 1944 V Invenior MAHJFRED T HOTFMAM" y 047* 1 A for ireys move grease, dirt, pitch,

Patented Aug. 16, 1949 METHOD OFFICE a CLEANING Manfred T. Hoffman, Newburyporig-Mass. Application August 8, 1944, Serial No. 548,620 '7 Y 3 Claims. (01. 8-142) This invention relates to methods and apparatus for dry cleaning wool and other animalfibres, hair, fur and skinsand other fibres and fibrous bodieswith adry cleaning solvent to repaint and other impurities. L

Heretofore, solvent drycleaning of such materials has been by batch methods in which a limited quantity of the material is immersed and sometimes agitated in a bath of the solvent, generally-in a heated, sealed vessel, for a long period of time. After the batch of material has been washed with the solvent, it is usually subjected to further treatment, normally in the same vessel, for recovering solvent therefrom in a closed solvent recovery system.

An object of the invention is to provide a novel method and apparatus for solvent cleaning such materials in a continuous operation to which the material is automatically continuously fed and from which cleaned material is automatically continuously withdrawn, which is speedier, easier to operate and control, requires less hand labor and is less costly than prior methods. Another object isto provide such a method and apparatus with which an improved cleaning action of the solvent is obtained. Another object is to provide such a method and apparatus whichare effective for simultaneously extracting the grease, pitch and paint from raw wool, Still another object is to provide such a method and apparatus with which the used solvent can be substantially fully recovered continuously and automatically and purified for re-use, with recovery of extracted grease as a byproduct.

Any suitable dry cleaning chemical or solvent, or mixtures thereof, may be used. Examples of suitable solvent are chlorides of the hydrocarbons having more than one carbon atom such as trichlorethylene, 'perchlorethylene, dichlormethane, carbon tetrachloride, and tetrachlorethylene; also solvents such as dimethylketone, tretrahydronaphthalene; and cyclohexanol; also Stoddard solvent, gasoline and solvents of the naphtha family, although this latter cleaning zone in which fresh solvent is applied to one or both of its surfaces by spraying, dipping, flowing or brushing the layer, while wet with solvent, and while so disposed that the solvent is free to drain therefromfls subjected to repeated intermittent squeezing action and preferably also to a workinga'ction which preferably includes both repeated alternate opposite flexings of the layer transversely of'its lengthand 'repeated rubbing of its surfaces under pressure, preferably in opposite directions.

I have found that by-su'chtreatment the material canbe cleaned of grease, pitch and like impurities in generally lesstime, and more adequately than with the conventional solvent bath process. Moreover, the process can be performed as a continuous operation with substantiallycomplete automaticfeed' and control by means of novel apparatus of the invention hereinafter described.

' Preferably the process is conducted with substantially complete recovery of-us'ed solvent and also of extracted impurities pf the material which form valuable by-products such as lanolin and other greases. This is accomplished by conducting the cleaning-operation ina closed chamber in which theused solvent and its fumes are confined for intermittent or continuouswithdrawal in a suitable solvent purifying and recirculating system. In addition, the material after leaving the cleaning zone is preferably subjected to further treatment ina closed chamber for removal and recovery of substantially all absorbed solvent. 7

The preferred apparatus ofthe invention for conducting the process as a continuous cleaning operation includes, in the cleaning zone, a long succession of alternate upper and lower rollers between which the layer of material passes, and which are rotated'to advance the layer therebe tween. Each roller of the upper or lower set is arranged between the adjacent two rollers of v the other set with their axes so spaced apart group is less desirable because of relatively high infiammability.

In the method of the invention, the material is subjected to cleaning while in the form of an elongated layer whichmay be, according to the nature of the .materialbeing treated, a hat or felt or bodies of unwoven, unspunfibre's or hairs, one or more thicknesses of a woven fibrous fabric or a succession of individual furs lor. skins. This layer of materialisthen advanced through a vertically that the layer of material passes over them in a sinuous path producing the alternate opposite transverse fiexings of the layer, and with their axes so longitudinally spaced that the layer is squeezed as it passes between their opposed surfaces. The rollers, in addition to their rotary movement which advances the layer of material, are preferably also given an oscillatory movement, for example'anfopposite relative endwise oscillation oflsuccessive rollers, which further works the-material layer by rubbin and scrubbingit. Means-are provided for substanparatusof Fig. 1. In

"fibrous materials may be subjected'to' crushing and dusting operations, with or without a preceding carbonizing step, to break down and shake out residues of pigment of paint and tar, shives ratus for the cleaning and solvent recovery ap- Fig. 2 solvent supply tanks for clean solvent are shown at 60 equipped with valved outlets 62 at the base through which solvent flows-into supply pipe 28 of the cleaning apparatus through which it ispumped by pump '63.

The drain pipe 34 for the used solvent liquid'of the cleaning apparatus is connected to a valved inlet 64 of a distiller 68in which the liquid is distilled to separate the solvent as a volatile vapor from the dissolved grease, paint and other impurities, and to which the used solvent is pumped by a pump 65. A filter (not shown) may be included in the pipe line 34. The solvent vapors from the distiller flow through a chimney pipe-68 into vapor collecting pipe 38 in which they are mingled with solvent vapors recovered from the chambers I and 40 and pumped by a pump 69 to a condenser where they are condensed to liquid form. The condensed, purified solvent liquidis recirculated to the containers 80 through pipe I2 and valved branch inlets 14 by pump II, either.

directly as shown, or through one or more oil scrubbers.

The grease and other impurities separated from the solvent in distiller 66 may be withdrawn periodically through a suitable piping system (not shown)-.

Figs. 3 and 4 of the drawing show in moredetail one form of worker roller mechanism suitable for the cleaning apparatus and method of the invention, the worker rollers in thisinstance having the preferred lateral or endwise reciprocal working orrubbing movement. V

As-shown in these figures, the: roller mechanism has 'a bed frame. I00 at the ends of which are vertical supports I02 (Fig. 3) having tubular upper ends on which are slidably mounted the ends of an upper frame I04. Frame I00 has fixedly mounted thereon transverse rods I06 on which is slidably mounted, by means ,ofcollars I08 a lower roller carrying subframeIIO. Similarly, frame.

I04 has fixedly mounted thereon transverse rods H2 on which is slidably suspended, by means of collars II4, an upper roller carrying sub-frame H6. The upper and lower banks of working rollers II8, which correspond to those diagrammatically indicated at 20 in Fig. 1, are mounted on shafts I20 which are rotatably journaled through the opposite side members of sub-frame I I6, I I0, respectively, and held therein by collars I22 at opposite sides of said members. The roller shafts I20 have fixed thereto, at one end, worm gears I24. Rotatably journaled through supporting arms I26 fixed to the corresponding side member of the upper and lower sub-frames H6, H0 are a pair of drive shafts I28 carrying worm gears I30 which mesh with the worm gears I24 of the upper and lower banks of rollers respectively. The upper drive shaft I28 has a driving sprocket I32 connected by chain I34 to a sprocket I36 on a main drive shaft or motor shaft I38 rotatably mounted on a lateral extension, above the sub-frame I04, of a fixed vertical frame I40 at one side of bed frame I00. Lower drive shaft I28 has a driving sprocket I42 connected by chain I44 to a second sprocket I46 on upper shaft I28.

1 particles clinging to the rollers. v

at opposite sides of shaft -which is 'slidable on said supports, rests. frame is yieldably urged against. said stops by supports. The surface 2 Also rotatably mounted onjframe I40 is ashaft I48, driven by sprocket and chain connection from shaft I38,1 and carrying a crank disk I50 having pivoted thereto one end of a crank arm I52. The other .end ofarm I52 is pivoted to a lever I54 pivoted between its ends ona shaft I56 fixed to frame I40. A pair of levers I58, I60 have one end pivotally connected to lever I54, respectively, I56. The opposite end of lever I58 is pivoted at I62 to sub-frame II6 while the lever I80 has its opposite end pivoted at. I84 to sub-frame I I0.

Rotation of shaft I48 rocks lever I54 by means of crank arm I52 so that the levers I58, I60 are reciprocated endwise in opposite directions, which 'inturn causes the sub-frames H0, H8 and their banks of rollers I I8 to slide to and fro, oppositely,

on rods I06 and H2, respectively, endwise or axially of the rollers II8. Roller drive shafts I28, being carried by the respective sub-frame IIO, H5, remain in driving engagement with the roller worm gears throughout this endwise reciprocation so that the rollers are continuously rotated, the chain drive to the upper shaft I28 having sufficient flexibility to permit this movement without disturbing the drive. I l l The minimum spacing. between the two. beds of rollers is adjustable by means of.adju stable stops I68 (Fig. 3) on thetubular upper ends of supports I02, on which the upper frame I04, Said springs I88 surrounding the supports above the frame and hearing at opposite ends against the frameiand against collars I10 adjustable on the of the rollers H8 is kept clean by means of scrapers or brushes which-remove dirt As shown more particularly in Fig. 3, the rollers II8 of the lower .bank are-eachprovided with a fiat, vertically 1 arranged scraper blade I80 which is fixedly connected'at its ends to frame I I0 and disposed below the rollenwith its scraping knife edge closely clearing the under surface of the roller. The dirt scraped off the rollers by these scrapers falls into the solvent collecting basins below the rollers.

' The rollers of the upper bank are also provided ;:,with scrapers I82, these, as shown in Fig. 3, being helically turnedabout the roller surface from -th eir ends toward the middle so that their outer ends are below their central portion. This enables the dirt scraped from the roller surface to clear longitudinally of the scraper blades over their lower outer ends where it can drop into the collecting basins below the roller bed free of the layer of material being cleaned and of the lower rollers. Scrapers I82 may, as shown, be supported by connection at their ends to the frame I I6.

Rollers I I8 may have smooth surfaces as shown, or they may be roughened as by the provision of longitudinal grooves, or both longitudinal and radial grooves, or by the provision of ribs.

While it is preferred to produce the working rubbing action upon the layer by an endwise oscillation of the rollers as by the mechanism herein specifically illustrated, a like effective action may be produced in other ways. For example, a similar effect may be produced by rotating successive rollers of the two banks in the feeding direction at slightly different peripheral speeds. This may be by rotating all the rollers of one bank at slightly slower speed than the rollers of the other bank but is better accomplished by rotating the rollers of the two banks at variant speed within each revolution, as Jay. 7 an eccentric drive to the roller drive shafts, the variant drive-to the twobanks being out of phase. in either case, theeffect is to produce arubbing,

scrubbingaction-on the surfaces of the layer oppo- J sitely in the direction of travel of the layer, insteadoftransversely thereof as with the mesh.-

anism shown.

It will beunderstood that by illustrating herein preferred-forms ofmechanism for practicing the process, -I do not intend to limit the invention thereto, but only as maybe required bytheappended claims.

I claim:

'1. "The method of drycleaningand. degreasing a material of the nature of wool and otherfrbres andfihrous bodies, hair skins, fur and fabrics with -a dry-cleaning grease dissolving solvent --which comprises continuouslyadvancin-g the material -in layer iorni'through an elongatedcleans ng zone asinuous path andtherein feeding solvent at -a plurality of longitudinally spaced points through thelayer and draining .usedsoL- -vent'theretrom while at asplurality of points spaced longitudinally of the layer, subjecting the layer to simultaneous-rollingsqueezing and bend- =ing action andioslrnul-taneous reciprocal transverse rubbing and scrubbing actionrelatiye to said advancing faces. '2. Apparatus forzcleaning and .degreasing wool layer oppositely on its oppositesurand other materials with a dryecleaning, grease -dissolving solvent which comprises in combina- -tion, means for supporting and continuously .advaneing a layer of thelmateria'l including .-a first bed of rollers engageable with one surface of the layer and ascond :bed of rollers 'engageable with the opposite surface of the layer between rollers of said :first bed, .the beds of rollers being closely spaced and the adjacent'rollers -of-=the respective-beds being closely spaced. to squeeze the'layer between the rollers .of said two beds the rollers of said beds being "dis- -posed transversely of the path of-travel of-=the ilayer, means for rotating said rollers to advance the layer'therebetween, means for continuously oscillating all of-the rollers of one of said-beds endwise relative to adjacent rollers of the other "said bed-t0 exert transverse working pressure -on the layer-alternately in opposite directions and naeahs-pcnneetizigto a souroe of 'a said solvent .io suppo tin and .the can. its sur ac .oftll -l yerh tween ro l r lander pressure fer enemies said advent $9 in 'suriaee oi the layer w ile laye isact dnn .hrsaidrnl-l rs.

11er en ae able W 1 aseea i be o e ssess ble with aid-fir t bed, thebedsr r le s be n cl sely ollers o the es ectiv e .to queeze h leve two beds th re ief elis ersely o the .e are; mean fo retains ne t e a l ye he e e ween aid be s re a ive to ad acen e sa d ha t xe t op it th .on q ite urfac s'of th ppn s te di e ions m n The following reference are of record in the Number Name Date 11:1313 K --Brown Jan. 31,1871 4 25,5 18 ZDeForest 'Apr. 9, 1872 174,04 -W-ilson Feb. .22, 1876 220,208 Lockwood -Sept. 30, 1879 -:534,027 Anderson Feb. .12, 1895 579,524 Turney Mar. 23, 1897 65?;401 Bel-tzer June 4,1901 895L399 'Shuman Sept. 22, 1908 899,440 Shuman Sept. 22', 1908 1,006,726 Grosto-n .Oct. 24, 1911 1,155,610 craven' Dec. 28, 1915 1,861,490 Butterwor-th s June- 7, 1932 1,934,:749 -'-=I-in'gle -Nov. 14,1933 2,196,695 Davies' Apr. 9, 1 940 i can. s lely ee i l tin i ll i th r llerso one o ro e n h -0th. -.-v rl$. ng p ess re i l se alte nate no neet ns to assume q a sa s v nde ,n s ur ior app in said solv nt to a fac o 

